{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,7]],"date-time":"2025-10-07T04:40:07Z","timestamp":1759812007037,"version":"build-2065373602"},"reference-count":58,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2025,10,4]],"date-time":"2025-10-04T00:00:00Z","timestamp":1759536000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"DST"},{"name":"Water Technology Initiative","award":["DST\/TMD\/EWO\/WTI\/2K19\/EWFH\/2019\/90"],"award-info":[{"award-number":["DST\/TMD\/EWO\/WTI\/2K19\/EWFH\/2019\/90"]}]}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["Molecules"],"abstract":"<jats:p>This study explores the use of lignocellulosic Tectona grandis seeds (TGs), hydrochar (HC-230-4), and activated carbon (AC-850-5) produced via hydrothermal carbonization and followed by CO2 activation for removing acridine yellow G (AYG) and acridine orange 14 (ABO) from water. HC-230-4 showed a rich presence of surface functional groups and irregular morphology with some sphere-like structures. In contrast, AC-850-5 exhibited a much higher surface area (729.7 m2\/g), though with fewer surface functional groups than HC-230-4. The batch method was used to study the effects of contact time, pH, dye concentration, and temperature. Among the materials, AC-850-5 showed the highest adsorption capacity of 198 mg\/g for AYG and 171 mg\/g for ABO at 25 \u00b0C, around 12% higher than commercial activated carbon. The adsorption process was spontaneous and endothermic, fitting well to the Langmuir isotherm model, suggesting monolayer coverage. The adsorption kinetics followed the pseudo-second-order model, indicating that the rate depends on the surface site availability. Intraparticle diffusion analysis further confirmed a multi-step adsorption process. These findings show the strong potential of TG-derived activated carbon as an effective and sustainable material for removing acridine dyes from polluted water.<\/jats:p>","DOI":"10.3390\/molecules30193989","type":"journal-article","created":{"date-parts":[[2025,10,6]],"date-time":"2025-10-06T13:33:41Z","timestamp":1759757621000},"page":"3989","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Assessment of Hydrochar and Porous Carbon from Tectona Grandis Seeds for Removal of Acridine Dyes"],"prefix":"10.3390","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4714-5672","authenticated-orcid":false,"given":"Shubham","family":"Chaudhary","sequence":"first","affiliation":[{"name":"Department of Chemistry, Gurukula Kangri (Deemed to be University), Haridwar 249404, India"},{"name":"Department of Chemistry, Motherhood University, Roorkee 247661, India"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1450-6689","authenticated-orcid":false,"given":"Monika","family":"Chaudhary","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Hariom Saraswati P.G. College, Dhanauri, Haridwar 247667, India"}]},{"given":"Sarita","family":"Kushwaha","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Motherhood University, Roorkee 247661, India"}]},{"given":"Vaishali","family":"Tyagi","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Motherhood University, Roorkee 247661, India"}]},{"given":"Shivangi","family":"Chaubey","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Motherhood University, Roorkee 247661, India"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2085-9157","authenticated-orcid":false,"given":"Isabel Pestana da Paix\u00e3o","family":"Cansado","sequence":"additional","affiliation":[{"name":"MED\u2014Mediterranean Institute for Agriculture, Environment and Development & Change\u2014Global Change and Sustainability Institute, Universidade de \u00c9vora, P\u00f3lo da Mitra, Apartado 94, 7006-554 \u00c9vora, Portugal"},{"name":"Department of Chemistry and Biochemistry, School of Science and Technology, University of \u00c9vora, Rua Rom\u00e3o Ramalho, n\u00ba 59, 7000-671 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8219-0148","authenticated-orcid":false,"given":"Evgeny","family":"Galunin","sequence":"additional","affiliation":[{"name":"Department of Organic and Ecological Chemistry, School of Natural Sciences, University of Tyumen (UTMN), 6 Volodarsky Str., 625003 Tyumen, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0802-5897","authenticated-orcid":false,"family":"Suhas","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Gurukula Kangri (Deemed to be University), Haridwar 249404, India"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"25194","DOI":"10.1080\/19443994.2016.1144534","article-title":"Adsorption of methylene blue onto activated carbon developed from biomass waste by H2SO4 activation: Kinetic, equilibrium and thermodynamic studies","volume":"57","author":"Jawad","year":"2016","journal-title":"Desalin. 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